The Database and Statistics Core of this Program Project is housed within the Department of Human Genetics in the UCLA School of Medicine. The Department encompasses the top 3 floors of the 10 year old Genetics Research Center in the Gonda Building. It has a 'state of the art' fully networked computer facility staffed by programmers and network managers through the Bioinformatics Core of the Department of Human Genetics. In addition, the UCLA Department of Human Genetics has developed as one of its strengths a substantial statistical genetics research group, focused on developing genetic analysis software within the Department. It includes Drs. Cantor, Sinsheimer, Horvath Papp, and Lange. Some of the most recent software developments in association analysis and quantitative trait linkage analysis by this group were motivated by data and research questions generated by the Program Project in its current cycle. The Database and Statistics Core hosts, and maintains the central servers for the Program Project. These include dedicated Database, Web, and Terminal servers located in a secure facility with professional-grade cooling and power. These machines have access to over 42 TB of storage capacity. The data is backed up incrementally each night to a RAID disk array and then fully backed up each weekend to a digital tape library. All servers are maintained at the current patch level of the operating system and application software. These dedicated servers are powerful machines as is required by the Program Project's data size and complexity. All machines will be highly secure while still allowing for easy access and maximum uptime. The Program Project scientists will also have access to a computational cluster of over 40 nodes maintained by the Human Genetics IT staff. This computational cluster has a full library of genetic applications, and is continually updated with current versions or any new packages that are requested. The machine used as the Terminal Server is an eight-way Xeon 3 GHz computer with 16 GB of RAM. Using standard Windows Remote Desktop Connectivity (RDC) software. Program Project data analysts will be able to access this computer from anywhere with an Internet connection, through personalized, password protected accounts. For optimal speed, all data analysis will take place on the Terminal Sen/er, not on the client's computer. There is a gigabit connection between this Terminal Server and the Database Server for fast data transfer. By using 64-bit versions of the Windows operating systems and the application software, the data analysts are assured access to virtually the full 16 GB data space for large-scale numerical computations Drs. Cantor, Sinsheimer, Horvath, Papp and Lange have offices and data analysis and computer labs in the building, along with the labs of Drs Pajukanta, Lusis and Reue, so discussions regarding design and data analysis are extensive and occur often. To facilitate data management and the performance of statistical and genetic analyses, databases and statistical and genetic analysis programs that are used by this Core are updated regularly. Additionally, publicly available genetic analysis programs are installed on the network as they become available through the worfdwide web. Data are backed up daily. In order to keep abreast of current developments in computing technologies, the computer system's hardware and software are upgraded on a regular basis in the UCLA Human Genetics Department Bioinformatics Core.